Glad to see you are up and running again.
You should be able to use the keyboard just fine. My introduction to MIDI was with a Radio Shack keyboard going through a MIDI/joystick adapter on a SoundblasterLive card. It is fun, and you don't have to worry about humanizing your track.
One problem you may have is with the latency of the Sigma Tel throwing you off. With a better, low latency sound card playing drums is a blast, and my daughter gets a kick out of watching me do Aynsly Dunbar impressions at my keyboard.
Does MC3 recognize your keyboard now? For any instrument sounds?
Are you using a soft synth(ie Edirol VSC) for your drum sounds, or the Microsoft Wavetable synth?
Do you know how to select the MIDI channel that the keyboard is transmitting on?
The answer to these questions will help me get a feel for where we are starting from.
My Soundclick Page SONAR Professional, X3eStudio,W7 64bit, AMD Athlon IIx4 2.8Ghz, 4GB RAM, 64bit, AKAI EIE Pro, Nektar Impact LX61,Alesis DM6,Alesis ControlPad,Yamaha MG10/2,Alesis M1Mk2 monitors,Samson Servo300,assorted guitars,Lava Lamp
Shimozu-Kushiari or Bob